Question
4. A random sample of 36 commuters in Chicago was taken. The sample mean of the...
4. A random sample of 36 commuters in Chicago was taken. The sample mean of the commuting times was 33.2 minutes and the sample standard deviation was 8.3 minutes.
a. Can the distribution of x ̅ be considered Nearly Normal? Why? (3)
b. Check for Independence. Explain your answer. (4)
c. Construct a 95% confidence interval. Show the formula and fill in all of the values. Calculations can be done using a calculator test. Give the answer to the nearest tenth of a minute. (10)
d. Give a verbal interpretation of the Confidence Interval. (10)
e. What is the margin of error? (7)
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